Method of making tubular members by progressive helical welding



3 Sheets-Sheet 1 H. P. VAN KEUREN Filed Dec. 16, 1943 METHOD OF MAKINGTUBULAR MEMBERS BY PROGRESSIVE HELICAL WELDING IllullnllllI-II-III-IIIII-I.

Jan. 6, 1948.

f/W Q vHENRY P.VAN KEUREN DECEASED MARIE $.VAN KEUREN ADMINISTRATRIXJan. 6, 1948.

METHOD OF MAKING TUBULAR MEMBERS BY PROGRESSIVE HELICAL WELDING FiledDec. 16,

5 Sheets-Sheet 2 Y P. VAN KEU E S VAN KEU gwucwlz DECEASEDADMINISTRATRIX Slice/M44 Jan. 6, 1948.

H P. VAN KEUREN METHOD OF MAKING TUBULAR MEMBERS BY PROGRESSIVE HELICALWELDING Filed Dec. 16, 1943 3 Sheets-Sheet 3 m mqwm 04". HENRY P.VANKEUREN DECEASED.

MARIE s. VAN mzunm ADMIMISTRATR'IX Patented Jan. 6, 1948 UNITED STATESPATENT OFFICE METHOD OF MAKING TUBULAR MEIVIBERS BY PROGRESSIVE HELICALWELDING Henry P. Van Keuren, deceased, late of Bloomfield, Ohio, byMarie S. Van Keuren, administratrix, Bloomfield, Ohio ApplicationDecember 16, 1943, Serial No. 514,554

7 Claims. (Cl. 219-10) This invention relates to the art of makingtubular members having unusual radial strength, and it is particularlydirected to a method for manufacturing gun barrels.

The 37 millimeter anti-aircraft gun and up to the largest present sizesof such types of weapon are now made of centrifugal castings. Theprocess of centrifugal casting is limited to the manufacture of guns ofnot over a 5 inch bore as an extreme, due to the length of the castingand inability to run the metal to such extreme lengths. Where forgedblanks are used in place of castings, a considerable amount of time islost in machining from the solid block. In the case of guns of largercaliber made of forgings by the built up method, an immense amount ofmetal removal and precision machine Work is required within closetolerances to provide for the shrink fits necessary.

A number of years ago the wire-wound gun was developed and, on a weightbasis, it was the strongest gun ever developed. 7 It had one seriousdrawback, however, and it was abandoned largely because of thisdrawback, namely, the tendency of the gun to droop or the bore to getout of line, due to lack of beam strength, which followed fromnon-continuity of metal between adjacent strands of wire longitudinallyof the gun. In other words there was no bond either between layers orbetween adjacent wires in the same layer. Attempts have been made tosolder the adjacent turns together where a brass or copper alloy wirewas used, such as in the days of brass cannon, but it is not practicablein the fabrication of the high power, alloy steel guns of today.

It is an object of the invention to provide a method of making tubularmembers of increased radial strength.

Another object includes a method of making steel gun barrels of anydesired size, utilizing the principle of the wire-wound gun, butcharacterized in that the gun barrels so made hav satisfactory beamstrength and are free from the droop otherwise present in guns of thewire- Wound type. Another object includes a method of making gun barrelsand tubular members which is simpler and less costly in time and laborthan conventional methods. A

Other objects include the provision of tubular members of increasedradial strength, and gun barrels of sufficient strength and. rigidity asto compare favorably with guns made by the conventional casting andforging methods.

Other objects will be apparent from the following description, havingreference to the accompanying drawing, in which:

Fig. 1 is a schematic diagram of the method of making the wrappedtubular members and guns of this invention, taken transversely throughthe tubular core I0;

Fig. 2 is a schematic diagram taken longitudinally through the tubularcore l0 and showing in detail the placement of the turns of the wrappingas they are welded in place; and

Fig. 3 is a cross-sectional view of part of a wrapped tubular member orbarrel illustrating different types of wrapping.

Referring to Fig. 1 a tubular core It, such as a seamless steel tube,either straight or tapered, is supported on rollers II and I2. A steelribbon I 3 with which the member i0 is to be Wound is passed through afurnace I 4 where it is preheated (e. g. to a, red heat) to reduce theamount of heating required in the welding operation. The ribbon l3passes between tension rollers l5 and [6, the roller I 5 being knurledso as to scrape off foreign matter and to roughen the surface of theribbon l3 to facilitate welding by increasing current density in spotsand to start minute arcs just ahead of the point of pressure of rollerll. From the rollers l5 and IS the hot ribbon 13 passes into contactwith the core ID, or layers of ribbon previously applied under heavypressure from a roller H. The roller ll, in addition to placing theribbon I3 against the core H] or other layers, supplies an intenseelectrical current whereby the ribbon I3 is welded in the area ofcontact between its roughened side and the ribbon layer underneath. Inthis way a tubular member is built up in which the covering is rigid andis under circumferential tension (or radial compression) in the same wayas a high caliber gun barrel.

In Fig. 2 the welding operation which takes place between the ribbon l3and the underlying layers is shown in more detail. The ribbon l3 shownhas a cross-section of a parallelogram and the pressure roller l1 forcesthe ribbon l3 simultaneously against the underlying layer l8 and theadjacent turn I 9. Electric current is supplied to the roller I! througha cable 20 which is connected to the bearing 2| of the roller IT. Theother electrical connection is made by means of a, shoe 22 which slidesin contact with the surface formed by the turns of the ribbon I3 andfollows right behind the roller [1.

In order that th ribbon l3 will be wound under tension, it is necessaryto provide means for rotating the core ID against the drag of thetension rollers l5 and It. For this purpose any large lathe, theheadstock of which is capable of grasping one end of th tubular core l0,and of subsequently holding the thicker, wrapped end of the tubularmember of the gun barrel, is satisfactory. The method of turning largecylinders against a torsional load is well understood in the art.

It is not necessary that an oblique ribbon be used in the formation ofthe tubular members and gun barrels described. For example a square orrectangular ribbon may be used, drojssQ sections of parts of two gunbarrels made'from two different types of ribbon are shown 3. Also shownby means of arrows 3 9 and t! is the direction in which the roller I'Ipresses the ribbon against the core H3, or underlying layers, and the.

adjacent turn. The angles shown are, of course, only approximate and arenot t all critical. practicable shape of wire or ribbon which may bereadily drawn or rolled and which may be wound, as laid, without voidsmay be used, and the heavier the ribbon, within limits, the more rapidwill be the process of building the gun barrel up to a definite size.

In the actual welding, the surface of the ribhon I3 and of the metal towhich it is to be welded may be further preheated by means of a flame(or other source of intense heat) at a point just ahead of the weld toinsure the best type of weld. However, for guns, the welds need not beperfect because the longitudinal stresses are low, and the gun does notrequire solid metal to prevent droop.

' As a result of the above process, gun barrels or other tubular membersof the kind described may be produced rapidly on relatively crudewinding machine made out of lathes, new r old. No great precision isrequired in the winding and machines may even be largely improvised ofstructural steel.

In cooling, the hot wire sets up shrinkage stresses similar to thoseobtained by shrink fits in the present types of built-up guns, but allpre-. cision machine work between components of eX i sting built-up gunsare eliminated, leaving only exterior, interior, breach and muzzlesurfaces to finish as required.

Many variations will be apparent to those skilled in the art and theinvention should not be limitedother than as defined by the appendedclaims.

What is claimed is:

1. Method of making a tubular member char: acterized by its relativelygreat radial strength compared to its weight which comprises wrap: pinga metal tube with a metal ribbon under pressure and progressivelyresistance weldin the ribbon to said tube and to the adjacentp'revieously Welded turn of ribbon as the ribbon is wound into place.

2. Method of making a tubular member char acterized by its relativelygreat radial strength compared to its weight which comprises helicallywinding in layers upon a metal tube a metal ribbon having sidesconforming in shape to those of adjacent turns in. the layer and to theunderlying'surface,'thereby to eliminate voids, apply: ing ressure tosaid ribbon as it is wound to press it simultaneously against saidunderlying sur face and the adjacent turn and simultaneouslyprogressively joining said ribbon to said underlying surface and to saidadjacent turn by resistance welding at the point of applied pressure.

3. Method of making gun barrels which comprises wrapping a steel tubeWith a steel ribbon under pressure and progressively resistance Weldthe, ib n to aid t nd t th adiacent previously welded turn of ribbon asthe ribbon is wound into place.

"4. Method of making gun barrels which comprises helically winding inlayers upon a steel tube a steel ribbon having sides conforming in shapeto those of adjacent turns in the layer and't'o the underlying surface,thereby to eliminate voids. applying pressure to said ribbon as it iswound to press it simultaneously against said underlyingsurface and theadjacent turn and progressively joining said ribbon to said underlyingsurface and to said adjacent turn by resistance welding at the point ofapplied pressure as the' b on is wound i t ce '5L'The method of making atubular memb r characterized by its great radial strength, whichcomprises wrapping a metal tube with a metal ribbon under pressure andprogressively resistance welding the turns of said ribbon to said tubeand to each other at the point where the ribbon first contacts the tubeand the previously wound convolution in a continuous seam as the ribbons ound 120 a 6, The method of making a tubular member characterized byits great radial strength compared to its weight which comprises,helically winding in layers upon a metal tubular core a metal ribbonhaving sides conforming in shape to those of adjacent turns in the layerand to the underlying surface thereof, thereby to mimimize voids,applying pressure to said ribbon as it is wound to press itsimultaneously against the underlying surface and the adjacent turn toeffect initial contact and progressively resistance welding said ribbonto said underlying surface and to said adjacent turn at the point ofinitial contact in a continuous seam as the ribbonis wound into place.

Th? me h of m k ng t ar embe which comprises wrapping a steel tube witha S ri bon u d r r u an progressively we i the turns o aid ri t a t band t t aq e i e sl el d tu in a 9niinuu 's am a t e ri bon is W un ntMA IE s. A KE aE-N. er ministw r W e Es te of Hen R Van rmit Pe f arREFERENCES GI'EED The following references are of record in the file ofthis patent:

UNITED. STATES BATENTS Number Name Date "13,984 Griifen Dec. 25, 1 855412363 Brown Oct. 8, 1889 417,800 Webb Dec. 24, 1889 485,624 Burton etal Nov. 22, 1892 6.6.6.450. Wilson Jan. 22, 1901 1,323,621 E wards Dec.2, 1.919. 1,665,851 Harris Apr. 10, 1928 2325341 H nse -e---.- Dee 3 .9

Certificate of Correction Patent No. 2,433,966. January 6, 1948.

HENRY P. VAN KEUREN It is hereby certified that the address of thedeceased inventor and of the administratrix in the above numbered patentwere erroneously described and specified as Bloomfield, Ohio whereassaid address should have been described and specified as Bloomm'lle,Ohio; and that the said Letters Patent should be read with thesecorrections therein that the same may conform to the record of the casein the Patent Oflice.

Signed and sealed this 25th day of May, A. D. 1948.

THOMAS E MURPHY,

Assistant G'ommissioner of Patents.

Certificate of Correction Patent No. 2,433,966. January 6, 1948.

HENRY P. VAN KEUREN It is hereby certified that the address of thedeceased inventor and of the administratrix in the above numbered patentwere erroneously described and specified as Bloomfield, Ohio whereassaid address should have been described and specified as Bloomv'ille,Ohio; and that the said Letters Patent should be read with thesecorrections therein that the same may conform to the record of the casein the Patent Oifice.

Signed and sealed this 25th day of May, A. D. 1948.

THOMAS F.- MURPHY,

Assz'stant G'ommz'ssioner of Patents.

